Mobile vaporizer system



AprilllO, 1951 v A, w, PECK 2,548,051

MOBILE VAPORIZER SYSTEM Filed Dec. 29. 1945 MVM ATTORNEYS Patented Apr.10, 1951 MOBILE VAPORIZER SYSTEM Alvin W. Peck, Bartlesville, Okla.,assignor to Phillips Petroleum Company, a. corporation of DelawareApplication December 29, 1945, Serial No. 638,405 6 Claims. (Cl.126-2712) This invention relates to vaporizers. In one of its morespecific aspects it relates to vaporizers for use with liquefiedpetroleum gases. In a still more specific aspect it relates tovaporizers which are adaptable for use in conjunction with tractorweedburner assemblies.

Flame methods for the killing of weeds have gained in usage in thecultivation of certain crops asa substitute for mechanical cultivatingor cutting methods and especially for hand methods. It is for thepurpose of further widening the use of llame methods of weed killingand/or cultivation that my invention is mainly directed.

One object of my invention is to provide a liquid hydrocarbon fuelvaporizer for use with Weed burning equipment on tractors.

Another object of my invention is to provide a liquid hydrocarbon fuelvaporizer for use with weed burning equipment on tractors wherein thevaporizer serves to vaporize fuel for the tractor as Well as for theburner.

Still another object of my invention is to provide a liquid hydrocarbonfuel vaporizer wherein an exhaust mui-ller mechanism serves to furnishheat for the vaporization of the fuel.

Still another object of my invention is to provide a liquefied petroleumgas vaporizer for use on a tractorweed burning assembly wherein thetractor muffler serves to furnish heat to vaporize liquefied petroleumgas for fuel for the Weed burner as well as for the propulsion of thetractor.

Still other objects and advantages of my invention will be obvious tothose skilled in the art from a careful study of thefollowingdescription, which taken in conjunction with the attacheddrawing forms a part of this specification.

In the drawing, Figure l represents digrammatically the assembledapparatus.

Figure 2 is a diagrammatic cross sectional View of a preferred form ofmy muffler-vaporizer apparatus.

Referring now to the drawing and especially to Figure l, a tractorassembly II is illustrated embodying the muffler-vaporizer shown indetail in Figure 2. The tractor itself may be substantially any kind ortype of tractor. It is adapted, however, for the use of a relativelylow-boiling type of hydrocarbon fuel. As, for example, equipment isreadily available, and in fact in common use, for the storage,transportation and use of liquefled petroleum gases, such aspropane,'=butane or mixtures of these.

Such hydrocarbons as propane or butane boil at temperatures below normalatmospheric temperature and therefore must be stored in pressure.

vessels. For the carburetion of such a fuel, and

'especially for the vaporization of the fuel at a relatively rapid rate,the vaporization equipment becomes so chilled due to the latent heat oi'evaporation that its usefulness becomes questionable. I have found thatby the use of a modified type muliier in combination with a conventionaltype muffler, that relatively rapid evaporation may be continued forlong periods of time thereby providing successful and practicaloperation.

Referring again to the tractor assembly II of Fig-ure 1, an exhaustmanifold pipe I2 is connected with a pipe I3 which is equipped with acutout valve I4, adapted to move around a pivot point I 5. This cutoutvalve is opened and closed through movement of a, rod I 'I which isattached to cutout valve I4 through a lever arm I8 and pivot member I6.In this assembly the cutout valve member I4, is of course, locatedinside ofthe pipe I3. The pivot member I5 extends through the walls ofthe pipe I3 and may be attached rigidly to the valve member I4. The armI8 is attached to one end of said pivot member I5 and is situatedoutside of the pipe I3. At the opposite end of the arm I8 is of coursethe pivot member I6 and at this Ip'oint is attached the cutout valveactuating rod This actuating rod I'I is moved by the action of a bellowsI 9, the operation of which will be hereinafter explained.

As mentioned hereinbefore one end of the pipey I3, which carries thecutout valve I4, is attached to the exhaust manifold pipe I2. The otherend of the pipe I3 is adapted to be attached to two pipes, identified bynumerals 20 and 2l. The pipe 2| is adapted to convey exhaust gases fromthe manifold I2 by way of cutout pipe I3 to a conventional muilier 23while pipe 20 carries exhaust gases through my vaporizer-muffler 22.From this vaporizer-muflier a pipe 3| serves as an exhaust pipe. y

Connected to the vaporizer-muffler 22 is a pipe 26, carrying a valve 32,which pipe is adapted for conducting petroleum gas fuel to a burnermechanism 33. An arm 34 serves mainly as a support to steadyJ the burnerduring operation and at times when'the tractor is in motion.

A pipe 2l is adapted to carry vaporized fuel from the vaporizer to acarburetor 35 for tractor power use and has a throttle valve 43positioned therein between said vaporizer and said carburetor. A pipe 25extends from the lower extremity of a pressure fuel tank 24 to thevaporizer 22 and has a cut-off valve 45 posi- 3 tioned therein. Fillervalve 48 is positioned in the inlet to pressure fuel tank 24.

The vaporizer-muffler mechanism 22 is shown in cross sectional detail inFigure 2. An interior portion 31 is for the most part a conventionalmufiier. This muffler portion is bounded by a sidewall 38 and end walls39. Several baffles 36. situated within the muiiier walls are intendedmerely to be diagrammatic since any desired type of baiiles may be usedwithin such a mufiier.

Outside the cylindrical muffler wall 38 is a concentrically spaced outercylindrical wall 40. This outer wall 40 and the muffler wall 38 are soarranged as to form an annular space 30 therebetween. This annular space30 is the actual vaporizing space for the vaporization of the liquefiedpetroleum gas, and heat for this vaporization is supplied through themufiler wall 38.

The tube or pipe 25 which carries liquid fuel from its storage tank 24to the vaporizing space 30 contains a iiow control valve 42 which inturn is connected by way of a tube 4I to the vaporizing chamber 30. Thisflow control valve 42 is so adjusted that as pressure in the vaporizingspace 30 reaches a predetermined maximum value, the valve operates 'tothrottle or to close off liquid fuel flow through pipe 25. Similarly.when the pressure of the vaporized gas reaches a predetermined minimumvalue, the valve 42 operates to open and permit fiow or to permitincrease of flow of liquid fuel to be vaporized. Such a flow controlvalve is known in the art and is readily obtainable from commercialsupply houses.

A chamber 28 contains such a material as ethylene glycol, and thismaterial has fluid communication w1th the bellows control apparatus I9through a tube 29. This fluid controller mechanism is intended as anoperating control to prevent overheating of the vaporizer mechanism.When the fluid in chamberr28 becomes heated, an increase of fluidpressure is transmitted by way of tube 29 to the interior of a mainbellows 43. When this pressurevincrease occurs the main bellows becomesextended and the rod I1 moves in a downward direction. To magnify thismovement of rod I1, an interior bellows 44 is installed in the mechanismas shown in Figure 2, and upon increase of fluid pressure in the spacebetween the two bellows, the top of the interior bellows also movesdownward. This combined movement moves rod I1 and accordingly pivotpoint I6 to such an extent that the cutout valve I4 rises to close offor to throttle the flow of hot exhaust gas from the manifold I2 to thevaporizer 22. Then when the vaporizer 22 cools to such an extent as tocause a decrease in pressure in the bellows assembly I9 to apredetermined value, the rod I1 and pivot I6 rise to open the cutoutvalve I4 and thereby increase iiow of hot exhaust gas through thevaporizer. commercially available bellows controllers are adjustable tothe extent that temperatures for opening valve I4 and for closing valveI4 may be determined by considerations for best overall operation. Otherfluid than ethylene glycol may be used in such a controller, as desired,and depending at least in part upon the type of controller selected andupon the temperature of operation.

In the operation of this vaporizer mechanism for the dual purpose asherein shown, liquefied petroleum gas to be vaporized passes frompressure storage tank 24 through pipe 25 and through the iiow controller42 into the vaporizing space 36 of the vaporizer 22. Heat from theengines exhaust gases passes through the wall 38 and in so doing causesevaporation of the liquid fuel in the chamber 30. If the flow of liquidentering chamber 30 through tube 25 is more rapid than the equivalentremoval of fuel vapor through pipes 26 and 21, pressure will build up inthe chamber 36 and be transmitted through tube 4I to cause the controlvalve 42 to close. And when pressure in the vaporizer 30 decreases to apredetermined value this valve 42 then opens to permit flow of liquid.Throttle valve 43 operates to prevent gas under excessive pressure fromreaching carburetor 35. Valve 43 causes a pressure drop 1n line 21 whenpressures therein are higher than those desired for operation ofcarburetor 35. Filler valve 46 operates to prevent the escape of gasthrough the fuel pressure tank inlet. If desired, pressure of fluidflowing into vaporizer-mufiler 22 can be greatly reduced by partiallyclosing cut-off valve 45.

During such times as when the weed burner 33 is not in operation theevaporation load on the evaporator 22 is relatively small, and theevaporator tends to overheat. This tendency is reduced or controlled bythe fluid-bellows control mechanism in such a manner that as the fluidin chamber 28 becomes hot, an increase of fluid pressure is transmittedthrough tube 29 into the bellows assembly. This assembly operates tolower the rod I1 and accordingly to raise the cutout valve I4 and tocause the exhaust gases from the engine to flow through the auxiliarymuffler 23 in place of through the evaporator 22. In this manner theevaporator 22 does not become overheated. Then as evaporator 22 cools,the fluid in chamber 28 cools and contracts reducing fluid pressurewhich allows rise of the rod I1. When rod I1 rises, the cutout valve I4lowers thereby causing all or a part of the hot exhaust gases to passthrough the vaporizer 22.

In this manner suicient exchange heat is readily available to vaporizesuiiicient liquefied petroleum gas to operate the tractor engine and theweed burner. Overheating of the vaporizer is guarded against and flow ofliquid fuel into the vaporizer is controlled.

The vaporizer-muffler unit 22 should be well constructed and especiallyso from the point of view of gas leakage. Exhaust gas should not leakinto the vaporizing chamber and likewise vaporized petroleum gas shouldnot leak into the muffler portion of the vaporizer.

Materials of construction may be selected from among those commerciallyavailable. They should be able to withstand gas engine muiliertemperatures, etc. The type and kind of control bellows may be selectedfrom among those available. Other means for operating the cutout valveI4 may be employed, if desired, but such means should preferably beresponsive to temperature of the vaporizer 30.

It will be obvious to those skilled in such art that many variations andmodifications of my invention may be made and yet remain within theintended spirit and scope of my invention.

Having disclosed my invention, I claim:

1. In a system having a liquefied petroleum gas storage tank, a separateliquefied petroleum gas vaporizer assembly having an internal combustionengine type muiiler with an engine exhaust gas inlet and an exhaust gasoutlet; a jacket surrounding said muier and forming an enclosed spacetherebetween, a liquefied petro- 15 leum gas conduit communicatingbetween said storage tank and said enclosed space, a ow control valvesituated in said liqueed petroleum gas conduit and actuated by pressurewithin said enclosed space, a gas outlet tube from said enclosed space,said engine exhaust gas inlet comprising a tube adapted forcommunication with an en gine exhaust manifold pipe and having a sideopening, and means for opening said side opening and closing saidexhaust gas inlet and opening said exhaust gas inlet and closing saidside opening to alternatively divert the gases from said muffler.

2. The liquefied petroleum gas vaporizer assembly of claim 1 wherein thegas outlet tube has a throttle Valve therein.

3. The liquefied petroleum gas vaporizer assembly of claim 1 whereinsaid means for opening and closing said side opening is adapted to beresponsive to the temperature of said jacket.

4. In a mobile vaporizer system including a gas consuming internalcombustion engine power plant; a fuel supply system comprising incombination a muffler having an inlet and an outlet, a jacketsurrounding at least a portion of said muier and forming an enclosedvaporizer space therebetween, an exhaust gas conduit connecting saidinternal combustion engine and the inlet of said muffler, a liquefiedpetroleum gas storage tank, a rst conduit connecting said storage tankand said jacket. a second conduit connecting said jacket and saidinternal combustion engine, a third conduitextending from said jacket,said third conduit being for connection with any additional gasconsuming device which is movable therewith, a ilow control valve insaid irst conduit, said flow control valve being responsive to pressurewithin said vaporizer space, a ow control valve in said third conduit;an exhaust gas outlet intermediate the ends of said exhaust gas conduit,a cutout valve in said exhaust gas outlet to divert gases from saidmuffler, and actuating means for opening and closing said exhaust gasoutlet connected to said cutout valve.

5. The mobile vaporizer system of claim 4, wherein said actuating meansis temperature responsive and extends between said jacket and saidcutout valve.

6. The mobile vaporizer system of claim 4, wherein a throttle valve ispositioned in said second conduit.

ALVIN W. PECK.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS

1. IN A SYSTEM HAVING A LIQUEFIED PETROLEUM GAS STORAGE TANK, A SEPARATELIQUEFIED PETROLEUM GAS VAPORIZER ASSEMBLY HAVING AN INTERNAL COMBUSTIONENGINE TYPE MUFFLER WITH AN ENGINE EXHAUST GAS INLET AND AN EXHAUST GASOUTLET; A JACKET SURROUNDING SAID MUFFLER AND FORMING AN ENCLOSED SPACEDTHEREBETWEEN, A LIQUEFIED PETROLEUM GAS CONDUIT COMMUNICATING BETWEENSAID STORAGE TANK AND SAID ENCLOSED SPACE, A FLOW CONTROL VALVE SITUATEDIN SAID LIQUEFIED PETROLEUM GAS CONDUIT AND ACTUATED BY PRESSURE WITHINAID EN-CLOSED SPACE, A GAS OUTLET TUBE FROM SAID ENCLOSED